The invention is directed to a plug-in connector for an electric toothbrush drive mechanism including an electric motor and a movement converter which is arranged between the motor and the plug-in shaft and sets the plug-in shaft in radial and longitudinal movement. The motor and converter are arranged in a housing, and the plug-in shaft, which is supported in a bottom surface of the housing, penetrates the bottom surface with its free end. The plug-in connector is detachably connected with the housing, and the plug-in shaft engages in the installed state with a connecting rod arranged in the interior of the plug-in connector, and the end of the connecting rod remote from the plug-in shaft is in a working connection with a radial drive.
An electric toothbrush comprising a drive mechanism consisting of an electric motor and a movement converter arranged between the motor and the plug-in shaft, as well as a brush body constructed as a plug-in connector, is known from EP-OS 0 357 863. The movement converter imparts upon the plug-in shaft both radial and longitudinal movement. The motor and the movement converter are arranged in a housing. In the installed state, the plug-in connector is rotatably connected with the housing of the toothbrush drive mechanism. A connecting rod is supported in the plug-in connector so that the connecting rod can execute only longitudinal movements, but not radial movements. The connecting rod is detachably connected via a catch connection with the plug-in shaft of the electric drive mechanism. A plurality of brushes are supported in the plug-in connector and are set in radial movement by the connecting rod by means of an eccentric drive. During operation, the movement of the plug-in shaft is transmitted so that the entire plug-in connector executes radial movements, while the longitudinal movements of the connecting rod allow the brushes to execute radial movements in addition after conversion at the eccentric drive. Since the entire plug-in connector, i.e. the housing and brushes, as well as the brushes can execute additional radial movements, these radial movements make it impossible to clean the intermediate spaces between the teeth or to polish the teeth even when only one brush is arranged. Moreover, the expenditure of energy for the drive mechanism is very high and is increased still further because of the soiling of the catch connection between the drive mechanism and plug-in connector due to toothpaste.